Intraorbital findings in giant cell arteritis on black blood MRI

Optic nerve sheath enhancement on orbital MRI in giant cell arteritis

BACKGROUND

Differentiating arteritic anterior ischaemic optic neuropathy (A-AION) due to giant cell arteritis (GCA) from non-arteritic anterior ischaemic optic neuropathy (NA-AION) may pose a diagnostic challenge. Our study aimed to assess the use of standard orbital MRI in distinguishing ocular manifestations of GCA from NA-AION.

METHODS

This study included 25 consecutive patients (11 GCA, 14 NA-AION) who underwent contrast-enhanced orbital MRIs within 3 months of symptom onset. Two radiologists blinded to clinical data independently evaluated MRIs for the enhancement of the optic nerve sheath (ONS) and other orbital structures.

RESULTS

On orbital MRI, ONS enhancement of at least one eye was more common in patients with GCA than NA-AION (64% vs 14%, p=0.02). ONS enhancement on MRI was seen in patients with typical ophthalmologic exam findings of A-AION as well as in GCA patients with other features of ocular ischaemia (eg, retinal artery occlusion). Among patients with GCA, ONS enhancement was bilateral in six of seven cases even when visual symptoms and signs were unilateral.

CONCLUSION

Patients with ocular GCA are more likely to have ONS enhancement on MRI compared with NA-AION. ONS enhancement was observed in (i) A-AION and other forms of ocular ischaemia, demonstrating the potential value of MRI in multiple orbital pathologies in GCA, and (ii) both the affected and unaffected eye, suggesting MRI may detect early subclinical ocular disease in GCA. These results highlight the potential value of adding orbital MRI to the diagnostic workup of ocular GCA.

Vessel wall MRI in giant cell arteritis: standardized protocol and scoring approach developed by an international working group

OBJECTIVES

There are an increasing number of centres performing research on high-resolution vessel wall magnetic resonance imaging (VW-MRI) in GCA. However, harmonized approaches to VW-MRI in GCA are lacking and are essential to performing multicentre studies. Using a data-driven, consensus-based approach, an international expert group developed a standardized MRI protocol and scoring system to advance multi-centred research in cranial GCA.

METHODS

A targeted literature review of VW-MRI in cranial GCA was conducted. A working group comprised of radiologists, rheumatologists and ophthalmologists with expertise in VW-MRI and GCA reviewed the results of the literature search, presented relevant data and images from their respective centres, and then reached consensus on recommendations related to key MRI structures, MRI sequences, scoring system and other important considerations.

RESULTS

A total of 21 relevant articles were identified and reviewed. Based on published literature, structures to be evaluated on MRI were categorized based on anatomic location (extradural cranial, intradural cranial and orbits) and prioritization (core vs elective). Essential and elective sequences to comprehensively image cranial and orbital structures while minimizing scan time were determined along with scoring systems to grade contrast enhancement.

CONCLUSION

This report describes a standardized approach to facilitate research of VW-MRI in cranial GCA that is the result of a multidisciplinary, international collaboration of experts in VW-MRI and/or GCA.

Imaging Findings in Giant Cell Arteritis: Don't Turn a Blind Eye to the Obvious!

Giant cell arteritis (GCA) is the most common primary large vessel systemic vasculitis in the Western World. Even though the involvement of scalp and intracranial vessels has received much attention in the neuroradiology literature, GCA, being a systemic vasculitis, can involve multiple other larger vessels including the aorta and its major head and neck branches. Herein, the authors present a pictorial review of the various cranial, extracranial, and orbital manifestations of GCA. An increased awareness of this entity may help with timely and accurate diagnosis, helping expedite therapy and preventing serious complications.

Enhancement within the orbits and superficial temporal artery: MRI clues to the diagnosis of giant cell arteritis

Purpose

Giant cell arteritis can have protean manifestations, many of them non-specific. We describe a patient whose initial presentation was most consistent with brainstem stroke, but who was ultimately diagnosed with and treated for giant cell arteritis.

Observations

A 76-year-old woman presented with abrupt onset diplopia, headache, nausea and vomiting. On presentation to the emergency department, she was diagnosed with a brainstem stroke and treated with tissue plasminogen activator. When her symptoms did not remit, closer inspection of her imaging revealed enhancement within the orbits and enhancement of her superficial and posterior temporal arteries. These findings led to the consideration of giant cell arteritis. Her signs and symptoms resolved with steroid treatment and a temporal artery biopsy was positive.

Conclusions and importance

This case highlights the emerging role of MRI and other imaging techniques in improving our ability to non-invasively diagnose giant cell arteritis.

Interdisciplinary approach in the management of visual loss in giant cell arteritis

Giant cell arteritis (GCA) is the most common vasculitis among older patients in western countries. A correct diagnosis permits the prompt initiation of glucocorticoids, which still represent the cornerstone of treatment. One of the most feared complications of the disease is sudden visual loss and other ischemic events causing visual disturbances. In these cases, an interdisciplinary approach between ophthalmologists and rheumatologists is crucial to avoiding any diagnostic delays and to permitting correct clinical assessment without subjecting the patient to unnecessary treatment. In this review, we discuss the main causes of visual disturbances in GCA, particularly the causes of sight loss, outlining the red flags that should raise suspicion in ophthalmologists and rheumatologists.

Clinical, laboratory, and orbital imaging features of giant cell arteritis in comparison to non-arteritic anterior ischemic optic neuropath: a single center case series

Background

Giant cell arteritis (GCA) is the most common vasculitis in patients older than 50 years and is considered a "do not miss" diagnosis. However, it remains a diagnostic challenge given overlapping clinical syndromes such as non-arteritic anterior ischemic optic neuropathy (NAION) and poorly explored imaging findings.

Materials and methods

In this retrospective study between the time period of January 2013 and December 2021, a total of 13 consecutive patients with a pathological diagnosis of GCA and 8 patients with clinical diagnosis of NAION were isolated. Demographic and clinical data for each patient were collected, including pertinent laboratory data. Pertinent physical exam data was also collected, including fundoscopic exam and visual acuity. Two neuroradiologist assessed the orbital MRI imaging findings of GCA and NAION for the presence and characterization of imaging abnormalities. Assessment for potential relationship between GCA orbital findings, laboratory and visual outcomes was performed. Finally, comparison between GCA and NAION imaging findings was performed.

Results

13 GCA patients were assessed. 9 patients had abnormal orbital findings. Of these 8 patients had bilateral orbital involvement The most common imaging findings was perineuritis of the optic nerve sheath, present in 7 patients. In total, 8 NAION patients were assessed. All patients demonstrate optic nerve involvement. The Snellen test was converted to logmar, and visual acuity was assessed for both NAION and GCA for each eye at diagnosis and at the last follow-up. There was no statistical significance for either eye for both GCA and NAION at initial diagnosis and final follow-up. In the 4 GCA patients with normal MRI findings and 9 GCA patients with abnormal MRI findings, there was no statistical significance between initial presentation and final follow-up visual acuity.

Conclusion

GCA and NAION are potentially overlapping clinical syndromes with different treatment approach and poorly explored imaging findings. Our case series assesses the orbital imaging findings of both syndromes while noting different imaging pattern of both on MRI, which can serve as a potential tool to aid in diagnosis of both. .

Imaging Challenges and Developments in Large-vessel Vasculitis

Vascular imaging is an integral part of large-vessel vasculitis (LVV) evaluation and management. Several imaging modalities are currently employed in clinical practice including vascular ultrasound, computed tomography angiography, MRI and magnetic resonance angiography, and 18F-fluorodeoxyglucose PET. Well-established roles for imaging in LVV include disease diagnosis and assessment of luminal lesions reflecting vascular damage. The ability of imaging to determine treatment response, monitor disease activity, and predict future arterial damage is an area of active research.

What is new in imaging to assist in the diagnosis of giant cell arteritis and Takayasu's arteritis since the EULAR and ACR/VF recommendations?

Over the past decades, fundamental insights have been gained to establish the pivotal role of imaging in the diagnosis of large-vessel vasculitis, including giant cell arteritis (GCA) and Takayasu's arteritis (TAK). A deeper comprehension of imaging modalities has prompted earlier diagnosis leading to expedited treatment for better prognosis. The European Alliance of Associations in Rheumatology (EULAR) recommended in 2023 that ultrasound should be the initial imaging test in suspected GCA, and Magnetic Resonance Imaging (MRI) remains the first-line imaging modality in suspected TAK. We summarize the recent advances in diagnostic imaging in large vessel vasculitis, highlighting use of combination imaging modalities, and discuss progress in newer imaging techniques such as contrast-enhanced ultrasound, shear wave elastography, ocular ultrasound, ultrasound biomicroscopy, integration of Positron Emission Tomography (PET) with MRI, novel tracer in PET, black blood MRI, orbital MRI, and implementation of artificial intelligence (AI) to existing imaging modalities. Our aim is to offer a perspective on ongoing advancements in imaging for the diagnosis of GCA and TAK, particularly innovative technology, which could potentially boost diagnostic precision.

Optic nerve sheath measurement to monitor disease activity in giant cell arteritis: a pilot study

INTRODUCTION/OBJECTIVES

Optic nerve sheath (ONS) enhancement using magnetic resonance imaging of the orbits was observed in patients with giant cell arteritis (GCA). We previously showed that ONS diameter (ONSD) by bedside ultrasound is increased in patient with active GCA. This study aims to assess whether ONSD decreases with clinical remission in patients with GCA.

METHODS

A prospective cohort study was conducted from June 2022 to January 2023. Patients who had an optic nerve ultrasound at GCA diagnosis as part of a previous crosssectional study were eligible. Optic nerve ultrasound was performed by the same investigator at diagnosis and month 3. ONSD (includes the optic nerve and its sheath) and optic nerve diameter (OND) were measured. Descriptive statistics for baseline characteristics and paired sample t-test were performed to assess the mean difference in OND and ONSD between diagnosis and month 3.

RESULTS

Nine patients with GCA were included. The median age at disease onset was 79 years (interquartile range (IQR) of 79-82 years), and 7 patients were males. All patients were in clinical remission at month 3 on prednisone (median dose of 15 mg/day, IQR of 10-25 mg). The mean ONSD was lower at month 3 (3.76 mm) compared to baseline (5.98 mm), with a paired mean difference of 2.22 mm (95% CI 1.41-3.03 mm, p < 0.001). As anticipated, OND measurements did not vary between diagnosis and month 3.

CONCLUSION

ONSD on ultrasound improves after 3 months of therapy in patients with GCA. A longer prospective study is required to determine if ONSD is useful to assess disease activity in GCA. Key Points • ONS ultrasound can identify patients with active GCA. • The ONSD on ultrasound is dynamic and improved after 3 months of GCA therapy. • ONS ultrasound may be useful to monitor disease activity in GCA.

Combined Orbital and Cranial Vessel Wall Magnetic Resonance Imaging for the Assessment of Disease Activity in Giant Cell Arteritis

OBJECTIVE

Acute visual impairment is the most feared complication of giant cell arteritis (GCA) but is challenging to predict. Magnetic resonance imaging (MRI) evaluates orbital pathology not visualized by an ophthalmologic examination. This study combined orbital and cranial vessel wall MRI to assess both orbital and cranial disease activity in patients with GCA, including patients without visual symptoms.

METHODS

Patients with suspected active GCA who underwent orbital and cranial vessel wall MRI were included. In 14 patients, repeat imaging over 12 months assessed sensitivity to change. Clinical diagnosis of ocular or nonocular GCA was determined by a rheumatologist and/or ophthalmologist. A radiologist masked to clinical data scored MRI enhancement of structures.

RESULTS

Sixty-four patients with suspected GCA were included: 25 (39%) received a clinical diagnosis of GCA, including 12 (19%) with ocular GCA. Orbital MRI enhancement was observed in 83% of patients with ocular GCA, 38% of patients with nonocular GCA, and 5% of patients with non-GCA. MRI had strong diagnostic performance for both any GCA and ocular GCA. Combining MRI with a funduscopic examination reached 100% sensitivity for ocular GCA. MRI enhancement significantly decreased after treatment (P < 0.01).

CONCLUSION

In GCA, MRI is a sensitive tool that comprehensively evaluates multiple cranial structures, including the orbits, which are the most concerning site of pathology. Orbital enhancement in patients without visual symptoms suggests that MRI may detect at-risk subclinical ocular disease in GCA. MRI scores decreased following treatment, suggesting scores reflect inflammation. Future studies are needed to determine if MRI can identify patients at low risk for blindness who may receive less glucocorticoid therapy.

Orbital magnetic resonance imaging of giant cell arteritis with ocular manifestations: a systematic review and individual participant data meta-analysis

OBJECTIVES

We conducted a systematic review and individual participant data meta-analysis of publications reporting the ophthalmologic presentation, clinical exam, and orbital MRI findings in patients with giant cell arteritis and ocular manifestations.

METHODS

PubMed and Cochrane databases were searched up to January 16, 2022. Publications reporting patient-level data on patients with ophthalmologic symptoms, imaged with orbital MRI, and diagnosed with biopsy-proven giant cell arteritis were included. Demographics, clinical symptoms, exam, lab, imaging, and outcomes data were extracted. The methodological quality and completeness of reporting of case reports were assessed.

RESULTS

Thirty-two studies were included comprising 51 patients (females = 24; median age, 76 years). Vision loss (78%) and headache (45%) were commonly reported visual and cranial symptoms. Ophthalmologic presentation was unilateral (41%) or bilateral (59%). Fundus examination most commonly showed disc edema (64%) and pallor (49%). Average visual acuity was very poor (2.28 logMAR ± 2.18). Diagnoses included anterior (61%) and posterior (16%) ischemic optic neuropathy, central retinal artery occlusion (8%), and orbital infarction syndrome (2%). On MRI, enhancement of the optic nerve sheath (53%), intraconal fat (25%), and optic nerve/chiasm (14%) was most prevalent. Among patients with monocular visual symptoms, 38% showed pathologic enhancement in the asymptomatic orbit. Six of seven cases reported imaging resolution after treatment on follow-up MRIs.

CONCLUSIONS

Vision loss, pallid disc edema, and optic nerve sheath enhancement are the most common clinical, fundoscopic, and imaging findings reported in patients diagnosed with giant cell arteritis with ocular manifestations, respectively. MRI may detect subclinical inflammation and ischemia in the asymptomatic eye and may be an adjunct diagnostic tool.

CLINICAL RELEVANCE STATEMENT

Brain and orbital MRIs may have diagnostic and prognostic roles in patients with suspected giant cell arteritis who present with ophthalmic symptoms.

Orbital MRI Findings in a Patient With Giant Cell Arteritis (GCA): A Case Report

Giant cell arteritis (GCA) is a medium- and large-vessel systemic vasculitis. It is common among people aged 50 years and older. GCA presents with cranial manifestations of headache, visual symptoms, cerebrovascular events, and systemic manifestations. The diagnosis of GCA is confirmed with a positive temporal artery biopsy. Treatment of GCA consists of high-dose steroids with slow tapering over 18 to 24 months and steroid-sparing therapy to maintain remission. Due to the risk of the most feared complication of GCA, irreversible visual loss, once GCA is suspected, high-dose steroids should be commenced immediately, and a temporal artery biopsy should be done not beyond one to two weeks after starting steroids to avoid the effects of steroids on the result of the temporal artery biopsy. There are orbital radiological findings reported in patients with an atypical presentation of GCA on MRI; these findings include non-specific orbital inflammation, optic nerve inflammation, optic nerve sheath inflammation, and optic chiasm enhancement.

Giant Cell Arteritis: State of the Art in Diagnosis, Monitoring, and Treatment

Giant cell arteritis (GCA) is the most prevalent subtype of vasculitis in adults. In recent years, there has been substantial improvement in the diagnosis and treatment of GCA, mainly attributed to the introduction of highly sensitive diagnostic tools, incorporation of modern imaging modalities for diagnosis and monitoring of large-vessel vasculitis, and introduction of highly effective novel biological therapies that have revolutionized the field of GCA. This article reviews state-of-the-art approaches for the diagnosis, monitoring, and treatment options of GCA.

Imaging of giant cell arteritis - recent advances

Imaging is increasingly being used to guide clinical decision-making in patients with giant cell arteritis (GCA). While ultrasound has been rapidly adopted in fast-track clinics worldwide as an alternative to temporal artery biopsy for the diagnosis of cranial disease, whole-body PET/CT is emerging as a potential gold standard test for establishing large vessel involvement. However, many unanswered questions remain about the optimal approach to imaging in GCA. For example, it is uncertain how best to monitor disease activity, given there is frequent discordance between imaging findings and conventional disease activity measures, and imaging changes typically fail to resolve completely with treatment. This chapter addresses the current body of evidence for the use of imaging modalities in GCA across the spectrum of diagnosis, monitoring disease activity, and long-term surveillance for structural changes of aortic dilatation and aneurysm formation and provides suggestions for future research directions.